> This is only truly necessary as a mechanism to prevent automated signups. Only if there isn't some shared knowledge between the website and prospect. For ex

> This is only truly necessary as a mechanism to prevent automated signups. Only if there isn't some shared knowledge between the website and prospect. For example some niche websites that I use have locally-based challenges such as 'how many engines can be fitted to a Boeing 747-400'* or a short mathematical algebra to solve. Both approaches work without Javascript and without external support, just with a two-column table and a trusted group of challenge-creators. * it's more than four